Most cooling towers are classified as either open or closed. Open cooling towers are configured generally as crossflow or counterflow designs. Conventional crossflow cooling towers have the cooling water flowing downward with air flowing perpendicular to the cooing fluid flow. In contrast, conventional counterflow cooling towers have the cooling water flowing downward with the air flowing parallel to the water flow.
The fluid distribution systems in cooling towers are generally of two types: gravity and spray. Spray systems are normally used in counterflow towers while gravity systems are utilized in crossflow towers. In a spray distribution system, spray nozzles are mounted to the distribution pipes. In a gravity distribution system, hot water reservoirs (commonly referred to as a basin or pan) disposed above heat-exchanging material (commonly referred to as “fill” material) include orifices (holes, passageways) configured in the bottom of the basin that allow a gravity release of the water within the basin. In some systems, each orifice is configured with a “target” nozzle to manipulate the water as it falls on the fill material. As water is released and output through the orifices, the falling water contacts the heat-exchanging material below which assists in increasing the cooling rate of the water as it flows over the fill material.
As is well known in the art, the rate of cooling of the water is important. Efficiencies in the distribution system may increase the cooling rate or thermal performance of the cooling tower. Thus, an efficient hot water basin distribution system is important.
A conventional crossflow cooling tower typically includes two hot water basins 14, with each hot water basin located on opposite sides from each other and along an outer edge. FIG. 1 illustrates a portion of one hot water basin distribution system 12 on one side of a crossflow cooling tower 10. As illustrated, the hot water basin distribution system 12 includes the hot water basin 14 which is rectangular in shape, and further includes multiple outlet (discharge) pipes 16 spaced apart from each other. Each outlet 16 pipe includes an opening that is oriented to dispense water substantially vertically downward (substantially perpendicular to the horizontal). For each outlet pipe 16, a baffle 18 (in this case, rectangular shaped) and/or weirs are positioned around the outlet area in an attempt to provide more equal flow of water within the hot water basin 14.
The baffles are typically constructed to be raised above the bottom of the hot water basin a few inches or so. Without the baffles, the velocity of the discharged water as it spreads out through the hot water basin would be such that the water flowing through the bottom orifices (providing the gravity outlet to the wet deck) would be inefficient—as some orifices would output more or less water than others—resulting in thermal inefficiencies. This is undesirable. However, even with these baffle structures, water flow is relatively uneven resulting in less efficiency.
Accordingly, there is needed a system, method and apparatus for hot water distribution in crossflow cooling towers that increases water flow efficiency within the hot water basin and gravity distribution system to increase thermal performance of the cooling tower.